. Morphology of angiosperms (Morphology of spermatophytes. Part II). Angiosperms; Plant morphology. THE FEMALE GAMETOPHYTE y:> increased remarkably in size, and after fertilization the cells increase rapidly and divide, forming a group of eight or more cells with remarkably large nuclei. In addition to these three monocotyledonous families, a prominent antipodal region has been found in Triglochin maritime/, (Hill76), in which there are three to fourteen cells; very large but undivided antipodals have been found in Lilaea (Campbell56), Commelina (Guig- nard12), Ornithogalum, Gladiolus, and
. Morphology of angiosperms (Morphology of spermatophytes. Part II). Angiosperms; Plant morphology. THE FEMALE GAMETOPHYTE y:> increased remarkably in size, and after fertilization the cells increase rapidly and divide, forming a group of eight or more cells with remarkably large nuclei. In addition to these three monocotyledonous families, a prominent antipodal region has been found in Triglochin maritime/, (Hill76), in which there are three to fourteen cells; very large but undivided antipodals have been found in Lilaea (Campbell56), Commelina (Guig- nard12), Ornithogalum, Gladiolus, and Crocus (Mottier36), Narcissus and Iris (Guignard 12), and Bomulea (Ferraris 120) ; and Ikeda 106 reports that in Tricyrtis the antipodals fill up the " chalazal protuberance," become elongated with it, and reach their maximum length just before fertilization. Among the Archiehlamydeae, the Ranunculaceae are espe- cially characterized by the activity of the antipodal cells, shown both by their great size and multinucleate condition, and also by their divisions. We have records of twelve genera, and in all of them the antipo- dals are conspicuous. In 1ST!.* Strasburger 5 reported the an- tipodals of Myosurus as very prominent, and in 1882 Guig- nard 12 described the antipodals of Erianihis as large, those of Clematis as very large and bi- nucleate, and those of Hepatica as forming a great group and becoming multinucleate after fertilization. In 1800 Wester- maier 23 reported large antipo- dals in Ranunculaceae, among them Nigella; and in 1895 Mottier 3rj investigated a num- ber of genera and described the antipodals of Delphinium tri- corne as very large, growing with the embryo-sac, and persisting till after fertilization; those of Callha palustris as large, pyriform, and multinu- cleate; those of Aquilegia canadensis as growing enormously. Fig. 46.—Aconitum NapeUus. Longitudi- nal section of embryo-sac after fertili- zation, showing the three very large antipodals :
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Keywords: ., bookauthorcoulterj, bookcentury1900, bookdecade1900, bookyear1903
